Revelation 11:3-7

3 I will give power to my two witnesses, and they will prophesy one thousand two hundred sixty days, clothed in sackcloth."  4 These are the two olive trees and the two lampstands, standing before the Lord of the earth.  5 If anyone desires to harm them, fire proceeds out of their mouth and devours their enemies. If anyone desires to harm them, he must be killed in this way.  6 These have the power to shut up the sky, that it may not rain during the days of their prophecy. They have power over the waters, to turn them into blood, and to strike the earth with every plague, as often as they desire.  7 When they have finished their testimony, the beast that comes up out of the abyss will make war with them, and overcome them, and kill them.